Conventionally, if a storage capacity needs to be increased, a user has to open a computer casing in order to install or replace a hard disc drive with larger capacity. However, it is difficult and complicated for an ordinary user who is not familiar with computer hardware to do the installation or replacement, and the hardware may even be damaged due to the user's unskilled operation.
To resolve the above problems, interface specifications such as USB and IEEE1394 are provided. The storage device is connected to a computer through the interfaces to increase the storage capacity conveniently. As the requirements of speed and capacity are getting higher and higher, data storage media have been developed from floppy disc, memory card, CD, DVD to external/internal hard disc drive.
The universal serial bus (USB) specification, which provides external peripheral equipment with a standard output/input interface, was developed in 1996. Following the in-built serial advanced technology attachment (SATA) standard, the external serial advanced technology attachment (eSATA) interface specification was developed to provide a convenient use of external hard disc. The eSATA specification used for external storage device implements high-efficient external storage, not only increasing storage capacity but also achieving excellent transmission rate.
The external storage device (such as but not limited to hard disc and optical disc drive) support many connection interfaces such as but not limited to USB, 1394, Internet small computer system interface (iSCSI), and SATA. The external storage device is connected to the PCI/PCIE bus of the computer host through a bridge interface. Exemplarily but not restrictively, the bridge interface may be realized by an add-on card for the translation between different standards.
In application, the external storage device goes with a dedicated application program. The dedicated application program sends vendor commands to the external storage device so that the external storage device may achieve product differentiation by performing the vendor commands. However, when the bridge interface, between the computer host and the external storage device, performs command translation, the vendor commands may be blocked by the bridge interface, so that the vendor commands and/or vendor data sent from the application program is not allowed to be transmitted to the external storage device through the bridge interface. Thus, the disclosure resolves the above problems. Even if the bridge interface does not support the vendor commands, the vendor commands will not be blocked by the bridge interface and may thus be transmitted to the external storage device from the host.